1. Field of the Invention
The invention relates to a device and a method for exhaust air processing, in particular, in clean room devices. The device comprises at least one fresh air supply and at least one exhaust air device which are connected to a work room, in particular, a machine room, storage room or a laboratory room, in which at least one processing device is arranged to which are connected at least one supply line and at least one exhaust air line. According to the method, supply air is supplied to a work room and/or at least one processing device and a pollutant-laden exhaust air stream that exits the processing device is supplied to a supply air flow.
2. Description of the Related Art
In the clean room technology, in particular, in the case of semiconductor manufacturing, wherein the semiconductor products to be processed are wet-etched, wet-cleaned, and/or chemically and mechanically polished, the corresponding processing devices are installed in a machine room or laboratory. It is required that generally from such rooms, in particular, in the presence of employees, a minimum amount of exhaust air must be removed which serves for removal of excess heat, for reduction of the concentration of risk materials or for fulfilling government regulations. Risk in this context means the sum of corrosion risks, contamination risks, and health risks, wherein corrosion relates to damage of the materials of the installation, contamination relates to soiling of a product that may be handled, and health risks relate to employees possibly being present. Many installations, in particular, in the area of clean room technology are however provided with a removal volume which is above the aforementioned limits. This is expensive primarily because the removed air must be replaced with freshly prepared ambient air.
It is known to return clean room air into the circulating air while pollutant-laden or risk-carrying air from processing devices is expelled into the exhaust air.
It is also known to return the risk-free air flows again into the room air and to clean the exhaust air of hoods in laboratories, typically 500 Nm3/h or less, via filters based on activated charcoal and to return it into the room air.
It is an object of the invention to configure a device and a method of the aforementioned kind such that the risk-carrying exhaust air flows can be cleaned and returned in a simple and inexpensive way.
This object is solved in accordance with the invention for the device of the aforementioned kind in that at least one filter is arranged in the exhaust air line of the processing device and that the exhaust air line is connected to the supply line of the processing device and/or of the work room. According to the method of the invention, the exhaust air at the processing device side is cleaned to remove high-risk pollutants before being returned into the air supply flow.
As a result of the configuration according to the invention, the risk-carrying air of the processing device is cleaned and returned. In this way, a large portion of the exhaust air of the processing device side can be reused so that it must not be replaced with fresh air. In this way, the amount of exhaust air as well as the amount of supplied fresh air can be reduced significantly which results in significant cost savings.